1. Field of the Invention
The present invention relates to apparatii for detecting the presence of various substances and, more particularly without limitation, to apparatii for detecting the presence of certain controlled substances in a liquid media.
2. Description of the Related Art
A common need in today's societies is the ability to at least qualitatively determine whether certain substances are present in a test specimen. One such determination exists when an individual is suspected of having illegally ingested a controlled substance. Since kidneys are adept at extracting the remnants of most illicit drugs from a bloodstream, a common procedure involves obtaining a urine specimen from a suspect. Various methods exist for determining the presence of illicit drugs in the urine specimen.
One commonly used procedure is to dip the end of a litmus strip in a test specimen wherein the litmus strip is designed to detect the presence of a particular drug in the specimen. When the end of the litmus strip is dipped in the specimen, the submerged end will exhibit a distinctive color change if the drug is present. If the anticipated drug is not present, the submerged end of the litmus strip will not change color.
A plurality of litmus strips have been developed to detect the presence of various specific drugs in a urine specimen. For example, Branan Medical Corporation of Irvine, Calif. has designed Fastect® II sensors for detecting amphetamines, benzodiazepines, barbituates, cocaine, marijuana (THC), methadone, ecstasy (MDMA), methamphetamines, opiates, oxycodone, phencyclidine (PCP), tricyclic antidepressants, or buprenorphine. Test strips have also been developed to detect the presence of alcohol and/or adulterants such as creatinine, nitrites, oxidizing agents, whizzes, bleach, etc.
Most of the aforementioned sensors have a slidably displaceable protective sheath in a stowed configuration that normally surrounds a sensitive area of its test strip. Typically, the sheath is displaced to expose an end of the sensitive area prior to submerging the end thereof in the test specimen. After the end has been submerged for a specified period of time to thereby allow desired chemical activity and color change to occur if the anticipated substance is present, the end is withdrawn from the specimen and the sheath is displaced to again surround the sensitive area.
It is extremely important to ensure the accuracy and reliability of such a test, and to preserve the results of the test for subsequent verification if necessary. Therefore, non-contamination during the test is absolutely essential. Unfortunately, many of the steps taken during a test with such a test strip may create a basis for challenging the results of the test.
For example, improper handling during various stages of a test could lead to possible contamination and degradation of the validity of the test while:
(a) displacing the protective sheath to expose the sensitive area of the test strip;
(b) inadvertently submerging into the test specimen more or less than the recommended length of the sensitive area of the test strip as specified by the manufacturer of the test strip;
(c) inadvertently allowing the end of the sheath to either touch the surface of, or be partially submerged in, the test specimen wherein urine adheres to the sheath;
(d) inadvertently allowing the sensitive area to be submerged in the test specimen for a longer or shorter period of time than specified by the manufacturer of the test strip; and
(e) returning the sheath to its stowed configuration to again protectively surround the sensitive area of the test strip.
If more than one substance may be present in the test specimen, a complete analysis requires that a different test strip designed for each of those substances be submerged in the specimen, which tests are generally conducted sequentially. Each such test requires a similar length of time to properly expose each of the different test strips to the specimen. The more individual tests that must be performed, the longer it takes to complete all of the tests of a given specimen from an individual.
Not uncommonly, when tests need to be conducted for one individual, they also need to be conducted on test specimens taken from several individuals at the same time. Conducting complete tests for each of several individuals obviously would require a substantially longer period of time than it would take to complete tests for only one individual. For example, a company or agency may require all job applicants as a condition of employment, or employees as a condition of continued employment, to successfully pass a drug test. Under those circumstances, tests may need to be performed on a large number of individuals. Unfortunately, the longer the time span between the beginning of such tests and completion of the final determination and memorialization of the test results may raise legitimate concerns regarding potential contamination and reliability of the results.
As a result, several technicians working in an assembly line-like fashion may be used to pass the various strips from one to another in order to reduce the time required to fully complete all tests. In so doing, such handling between technicians may further compromise the integrity of the results.
Therefore, what is needed is an apparatus wherein a technician working alone can simultaneously conduct tests on a test specimen with a plurality of test strips having sensitive areas while the test strips are retained separated from each other and while handling by the technician occurs remotely from the sensitive areas at all times.
What is also needed is an apparatus wherein a technician working alone can simultaneously displace the sheaths of a plurality of test strips to thereby expose predetermined lengths of the sensitive areas thereof from their protective sheaths while the test strips are retained separated from each other and while handling by the technician occurs remotely from the sensitive areas at all times.
What is further needed is an apparatus wherein a technician working alone can simultaneously submerge only lengths of the sensitive areas of a plurality of test strips in a test specimen as specified by the manufacturer of the test strips while the test strips are retained separated from each other and while handling by the technician occurs remotely from the sensitive areas at all times.
What is still further needed is an apparatus which prevents the sheaths of a plurality of test strips from touching the surface of, or being submerged in, the test specimen as the sensitive areas are being submerged in the test specimen to thereby avoid adherence of the test specimen to the sheaths.
What is still further needed is an apparatus wherein a technician is automatically alerted when the time specified by the manufacturer of the strips for emersion of the sensitive areas in the test specimen has transpired.
What is still yet further needed is an apparatus wherein a technician working alone can simultaneously withdraw the sensitive areas of a plurality of test strips from the test specimen while the test strips are retained separated from each other and while handling by the technician occurs remotely from the sensitive areas at all times.
What is still yet further needed is an apparatus wherein a technician working alone can simultaneously displace the sheaths of a plurality of test strips to again surround the sensitive areas while the test strips are retained separated from each other and while handling by the technician occurs remotely from the sensitive areas at all times.